The invention relates to a protective breathing mask having a connector housing for mask components, a mask body connectable to the connector housing and made of elastomeric material, a connecting surface extending about the periphery of the connector housing for a correspondingly configured cutout defined by a profile-reinforced portion of the mask body, and a connecting member for securing the profile-reinforced portion to the connecting surface.
A protective breathing mask of the above-mentioned kind is disclosed in European patent publication 329 941 B1. The known protective breathing mask has a connector piece in which a breathing connector, an inhalation valve, and an exhalation valve are accommodated. The outer surface of the connector piece is configured as a connecting surface for a mask body made of a flexible material. In the region of the connecting surface of the connector, the mask body is reinforced by a profiled configuration so that the mask has a certain stability as to form during assembly. The profile-reinforced portion of the mask body defines a cutout and is fastened by a clamp to the connecting surface of the connector.
The known connection by a clamp can be realized only for oval or circular connector housings in which the clamp can be mounted in a plane. Because of this pregiven outer contour of the connector housing, however, there are only a few degrees of freedom available within the connector housing for the arrangement of the breathing valves and the breathing connector relative to one another so that an optimal positioning of these components is often not possible.
It is an object of the invention to improve a protective breathing mask of the above-mentioned kind such that the connection between the mask body and the connector housing can be realized in a simple manner without having to provide certain preferred geometric shapes at the connecting location.
The protective breathing mask of the invention includes: a connector housing unit; the connector housing unit including a connector housing adapted to receive breathing mask components therein; the connector housing unit including an annular flange-like collar extending outwardly from the connector housing; the flange-like collar having a connecting rim; a mask body having a profile-reinforced portion; the profile-reinforced portion being configured to correspond to the connecting rim; a clamping ring having a cutout for holding the profile-reinforced portion; the clamping ring being formed to correspond to the connecting rim and having a connecting surface in direct contact engagement with the connecting rim; the connecting rim and the connecting surface conjointly defining an interface; and, joining means for joining the clamping ring to the connecting rim in the region of the interface to trap and hold the profile-reinforced portion therebetween.
The advantage of the invention lies essentially in that a plurality of connecting geometries can be realized by the combination of the invention of a clamping ring, in which the profile-reinforced portion of the mask body to be connected to the connector housing unit is initially secured, and the subsequent connection of the clamping ring to the connecting rim disposed spaced from the connector housing. The connector housing unit with the connecting rim as well as the clamping ring configured to match the connecting rim can be manufactured as injection-molded parts without being restricted to certain preferred geometries. For fixing the mask body portion defining the cutout in the clamping ring, the clamping ring is provided with a slot-like recess into which the profile-reinforced portion of the mask body is inserted.
Alternatively, it is also possible to provide the slot-like recess at the connecting rim of the connector housing unit and to initially fix the profile-reinforced portion at the connecting rim of the connector housing unit. The clamping ring can be attached at the connector housing unit at the common connecting surface between the connecting rim of the connector housing unit and the clamping ring, for example, by a snap connection. The elements of this snap connection can be directly formed, as is known in the art, on the injection-molded parts without incurring additional cost.
It is especially advantageous to select the materials of the clamping ring and of the rim such that a welded or adhesive connection can be produced at the connecting surface. An especially advantageous welding method is the so-called ultrasound welding method, and especially suitable materials therefor are polypropylene, polyamide and PVC.